HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 289/6/L1011    most recent 00250.2005v1 Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via ISI Web of Science (2) Citing Articles via Google Scholar Google Scholar Articles by Jain, D. Articles by Bates, S. R. Search for Related Content PubMed PubMed Citation Articles by Jain, D. Articles by Bates, S. R.

Pathways for clearance of surfactant protein A from the lung

Institute for Environmental Medicine, University of Pennsylvania Medical Center, Philadelphia, Pennsylvania

Submitted 9 June 2005 ; accepted in final form 4 July 2005

Uptake and degradation of ¹²⁵I-surfactant protein A (SP-A) over a 1-h period was studied in alveolar cells in culture and in isolated perfused lungs to elucidate the mechanism for clearance of the protein from the alveolar space. Specific inhibitors of clathrin- and actin-dependent endocytosis were utilized. In type II cells, uptake of SP-A, compared with controls, was decreased by 60% on incubation with clathrin inhibitors (amantadine and phenylarsine oxide) or with the actin inhibitor cytochalasin D. All agents reduced SP-A metabolism by alveolar macrophages. Untreated rat isolated perfused lungs internalized 36% of instilled SP-A, and 56% of the incorporated SP-A was degraded. Inhibitors of clathrin and actin significantly reduced SP-A uptake by 54%, whereas cytochalasin D inhibited SP-A degradation. Coincubation of agents did not produce an additive effect on uptake of SP-A by cultured pneumocytes or isolated perfused lungs, indicating that all agents affected the same pathway. Thus SP-A clears the lung via a clathrin-mediated pathway that requires the polymerization of actin.

clathrin-mediated uptake; actin; type II cells; macrophages; degradation; perfused lung

This article has been cited by other articles:

				S. R. Bates, A. S. Kazi, J.-Q. Tao, K. J. Yu, D. S. Gonder, S. I. Feinstein, and A. B. Fisher Role of P63 (CKAP4) in binding of surfactant protein-A to type II pneumocytes Am J Physiol Lung Cell Mol Physiol, October 1, 2008; 295(4): L658 - L669. [Abstract] [Full Text] [PDF]

				S. R. Bates, C. Dodia, J.-Q. Tao, and A. B. Fisher Surfactant protein-A plays an important role in lung surfactant clearance: evidence using the surfactant protein-A gene-targeted mouse Am J Physiol Lung Cell Mol Physiol, February 1, 2008; 294(2): L325 - L333. [Abstract] [Full Text] [PDF]

				A. V. Andreeva, M. A. Kutuzov, and T. A. Voyno-Yasenetskaya Regulation of surfactant secretion in alveolar type II cells Am J Physiol Lung Cell Mol Physiol, August 1, 2007; 293(2): L259 - L271. [Abstract] [Full Text] [PDF]